/Engine/Source/Runtime/GeometryCore/Public/MeshQueries.h
Compute the length for each edge and return the result as an array of Mesh.MaxEdgeID() size. When mesh is not compact, the length of the missing edges is set to -1.0
static void GetAllEdgeLengths ( const TriangleMeshType & Mesh, [TArray](API\Runtime\Core\Containers\TArray)< double > & Lengths, double & TotalLength )